Process of making door panels of fibrous materials



July 5, 1932. E. c. LoETscHER PROCESS OF MAKING DOOR PANELS OF FIBROUSMATERIALS 2 Sheets-Sheet l Filed Dec. l2, 1929 July 5, 1932 1 I E. c.LoETscHER 1,866,312

nm/Ma Mmmm 25 prescribed areas of the panel.

Patented July 5, 1932 PATENT OFFICE EMIL C. LOETSCHEB, F ID'UBUQUE, IOWAPROCESS OFMAKING DOOR PANELS 0F FIBROUS MATERIALS 'Application ledDecember 12, 1929. Serial No. 413,454.

6 iibre, and more particularly to a method for reproducing on thesurface of such articles not only the graining of the natural wood, 4butthe ornamental effect of the grain running in different directionsthroughout varous portions of the surface.

In a copending application, filed by me on even date herewith, Idescribe a process for manufacturing door panels and the like, in

which the ornamentation was carried out in v the surface contour as wellas in the treatment of the graining effect of natural woo-d. Forconvenience, the same or a similar door panel will be used for thepresent disclosure, which will be directed more particularly to thetreatment of the thin bakelized sheets grained and colored in imitationof a natura-1 wood and forming the surface layer of the composite panel,whereby the several grained areas are made to register exactly with theThe objects and purpose ofthe invention will more clearly appear fromthe description which follows, together with the figures of theaccompanying drawings, in which Figure 1 is a View in front elevation ofa door having a panel made in accordance with the process hereindisclosed;

Figure 2 is a view in cross section through the door;

Figure 3 is a perspective view of a continuous sheet of the grainedpaper used for the surface of the panel;

Figure 4 is a perspective view showing the manner in which thetransverse strips are cut from the grained paper;

Figure 5 is a view in elevation showing the effect of superimposing thestrips upon the main sheets of grained paper to reproduce the effect ofa mitered frame;

Figure 6 is a perspective view of relative positions of the severallayers Ofpaper; and Figure 7 is a view in vertlcal section through thelower die plate with the strips of paper attached thereto and the mainsheet in position to be applied over the plate.

The door of which the panel 1 of composite material forms the centralportion, composes an outer frame made up of stiles 2-2 and rails 3-3surrounding the panel. These stiles and rails are preferably of wood andare rabbeted about their inner edges to intert with a tongue la formedabout the outer edge of the panel. The panel 1 has a rectangular centralportion 1b of uniform thickness throughout but relatively thin ascompared with the rails and stiles, and an outer marginal portionincreasing in thickness from its inner to its outer edge by severalsteps in the form of a series of flat or beveled surfaces separated byabrupt narrow shoulders.

Moreover, these irregular surfaces meet at each corner of the panel atangles after the manner of a miter joint and for this reason thismarginal portion has the appearance of a mitered frame or mouldingbetween the outer frame of the door and the thin central panel. In fact,in an all-wood door the mitered frame or moulding members and thecentral panel are al1 separate pieces assembled and glued together, andwhich are replaced by the one-piece panel 1 having a compressed fibrousbase.

It may be stated in this connection that the mitered frame or mouldingbetween the outer frame of the door and the thin center panel could beeliminated so far as the structural features are concerned, but such adoor would be quite plain and unattractive, and therefore it has becomethe practice to .enhance the appearance of doors by the addition of theintermediate frame. This. frame may be more or less elaborate as tosurface contour, ranging from the. stepped, flat and beveled contour ofthe present disclosure to plain beveled surfaces, although these areinvariably mitered at the corners not only to give the effect vofsymmetry but also to take advantage of the contrast in the grainlng.Thus n a door of hardwood with a natural or varnished finish, the grainof the wood in the stiles 2, 2, the vertical members of the miteredframe and the center panel would run lengthwise or vertically of thedoor while the grain in the rails 3, 3 and cross members of the miteredframe would run transversely.

Hence, in making a composite panel the surfaces are preferably finishedto reproduce the same effect as would be found in a wood door, even tothe lines of the miter joints which are usually visible.

Having explained that the outer surface finish of the composite panel isobtained by the use of what is termed a bakelized paper, the method ofreproducing the desired ornamental effects will now be discussed.

Without going into detail as to the processing of the material of whichthe panel is made,.it is sufficient to state that the base of the panelis a suitable cellulose fibre, such as would be obtainable fromcornstalks, which having been reduced to a pulp, is formed into a mat,dried and eventually compressed in a hydraulic press to its final shape,as well as to a density comparable to that of solid wood. Prior to thefinal pressing operation, however, the surface of the fibrous mat iscoated with varnish and dried, a solution of bakelite varnish beingpreferably used. Then a layer of kraft paper is laid over the surface ofthe mat, this kraft paper having been coated with the same varnish. Andfinally, a layer of thin bakelized paperpainted and colored in imitationof 'the natural wood being reproduced, is laid over the sheets of kraftpaper and the assembled materials then compressed between the dies inthe press, the opposing faces of the dies having the surface contour ofthe panel cut or impressed therein. If the surface contour is somewhatelaborate necessitating the bending of the sheets of paper `aroundnumerous sharp angles, a dry molding mixture composed of equal parts ofbakelite and wood flour, is spread in a thin coating between thesurfaces of the mat and the layers of paper. The assembled materials areheated before the pressure is applied, whereby 'the varnish and themolding mixture are rendered plastic, which allows the sheets to takethe contour of the dies without tearing or distortion. So much for theprocess of manufacture which, of course, may be varied to `,suit theparticular working conditions.

Referring now to the treatment of the outer layers of bakelized paper,it may be stated that a thin grade of alpha-cellulose paper is used andin the course of its preparation is printed with an over-all design inimitation of the characteristic graining of a particular kind of wood,such as mahogany, walnut, etc., then colored or dyed to correspond tothe color of the wood, and finally subjected to impregnation by asolution of bakelite varnish, which is preferred because of itsexceptionally hard and wear-resisting qualities. The paper may also begrained by the use of graining rollers, the simplest method being tograin the paper uniformly so that it runs in the same directionlengthwise of the sheet as in Figure 3. With a quantity of this grainedpaper on hand, the rst step in preparing an outer layer for one face ofthe panel is to cut a sheet 5 to the length and width necessary to coverthe entire surface, with the grain running lengthwise. Now from the samematerial, two narrow strips 6 are cut from its side edge portion alonglines converging at angles of 45 (Figure 4) the length of these Stripsbeing equal to the width of the main panel sheet 5 and their width beingequal to the width of the end areas corresponding to the transversemembers of the mitered frame. These strips 6, one at each end,eventually are laid over and register with the main sheet 5, as shown inFigure 5. Ordinarily the paper is rendered more or less tranparent bythe bakelite impregnation, and to prevent the graining of the main sheet5 from showing through the superimposed strip 6, an intermediate strip 7is preferably placed between the two, as shown in Figure 6. Thisintermediate strip is a duplicate of the upper grained strip in shapeand size, but is preferably cut from a plain sheet of bakelized paper.

The superimposed layers of paper may be temporarily secured together bya suitable adhesive or by means of thin paper stickers, and theassembled panel sheet applied to the face of the mat and the wholeplaced between the die plates preparatory to the final pressingoperation in a hydraulic press, care being taken that the outer sheetregister with the impression in the die plates. The ymore satisfactorymethod, however, is to first apply the strips 6 and 7 directly to thedie plate and in register with the end sections of the irregularmarginal portions which form the mitered frame of the panel, fasteningthem in place as by stickers 8, as shown in Figure 7. Then the all-overgrained panel sheet 5 is laid over the die plate, and finally the matwith its covering of kraft paper.

Then the panel l has been nally compressed into the form shown inFigures 1 and 2 and fitted into the stiles and rails to form a completedoor, the superimposed strips 6 and 7 are embedded flush with the mainpanel sheet 5, thus giving the same effect as a mitered frame ormoulding, with the grain running crosswise at the top and bottom withthe grain in the vertical members of the frame, and the central panelextending lengthwise or vertically of the door. Likewise, the diagonalend edges of the strips by virtue of their perfect registration with thedie plate coincide with the lines of mitering and further give theappearance of an actual mitered frame or moulding.

There are other ways of obtaining the same results, namely, by producingsheets bearing an impression printed from a plate prepared from thephotographic negative of an actual wood panel. This, however, is arather costly process, unless a large volume of production isanticipated. Again, the sheets may. be prepared with grainmg rollers,using templets to mask off the areas at the ends for the cross grainingand then using a narrow graining roll to fill in these end areas. Thisrecess, however, requires special templets an graining rolls, andtherefore is not entirely satisfactory.

The advantage of the present process therefore is the simplicity andcheapness of practice, since no special equipment is required otherlthan a. supply of grained paper from which the strips are cut for thecross grained areas at the ends of the panel. Moreover, by fasteningthese strips directly to the face of the die, the chance ofmis-registration is practically eliminated.

I claim as my invention:

1. A process of'manufacturing a panel or the like of a compositematerial having a base of a compressible fibrous material consisting ofcovering the surface of the base material with a sheet of fibrousmaterial reproducing a natural wood finish with the grain extending inone direction and coated with a resinous substance, superimposingsmaller sheets of the same coated fibrous material upon saidfirst-mentioned sheet to cover predetermined areas with the grainextending transversely thereof, and compressing the base material andsheets of fibrous material.

2. A process of manufacturing a panel or the like of a compositematerial in imitation of a natural wood nel having a .mitered frame,consisting o preparing a mat of a compressible fibrous material,covering the surface of said mat with sheets of a thin fibrous materialcoated with a resinous substance and reproducing the natural wood lgraining, superimposing strips of the same fibrous sheet material uponthe first-mentioned sheets to reproduce mitered frame members alongopposite edge portions of the panel with the grain extendingtransversely to that` in the body thereof, and compressing the mat withits covering sheets in the presence of heat.

3. A process of manufacturing a panel or the like of a compositematerial in imitation of a natural wood panel having a mitered frameconsisting of preparing a mat of a compressible fibrous material,covering the surface of said mat with a sheet of relatively heavy papercoated with a resinous substance, superimposing a thin sheet of resinimpregnated fibrous material over the papercovered surface of said mat,the same representing a natural grained wood, superimposing strips ofthe grained sheet material upon the first sheet to reproduce the miteredframe members along opposite margins of the panel with the grainextending lengthwise thereof,

and compressing the assembled materials between die plates having theimpressions ofv the panel surfaces.

4. A process of manufacturing a panel or the like of a compositematerial havin a base of cellulose libre pulp capable of belngcompressed between die plates having the impression of the panel surfaceinthe opposed faces thereof, consisting of preparing a mat for the baseof said panel, covering the surfaces of the mat with thin sheets ofgrained fibrous material impregnated with a resinous substance with thegraining running lengthwise thereof, cutting relatively narrow stripswith mitered ends from the same grained fibrous material with the grainrunning lengthwise thereof, attaching said strips to said diel platesand in register with areas thereof corresponding to the marginal framemembers, and compressing the base material and the superimposed layersof brous material between said die plates.

Signed at Dubuque, Iowa, this 7th day of December, 1929.

" EMIL C. LOETSCHER.

